Cap for a marker pen



FIG. 1 is a perspective view as seen from the top, front and right side of a cap for a marker pen showing our new design;

FIG. 2 is a perspective view as seen from the bottom, front and left side thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right elevational view, the left elevational view being a mirror image thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom view thereof.

The broken line showing of a marker pen is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a “cap for a marker pen”, as shown and described. 